22 F550 rear differential problems
Specifically, the pinion bearing seat? I had one other person who said that their work truck, a 22 550 as well, had a rear pinion issue and found the case was machined improperly for the bearing seat and had to get a new axle housing to fix the problem.
Mine has had a vibration since new and now has 48k on it. I have had it to the local dealer (I live in a small town) who is absolutely unhelpful, telling me that I needed to buy a pallet of concrete before he would even look at that problem.
I have replaced and balanced the tires/had the wheels checked for round at a medium and heavy duty truck tire shop. I still had the problem. I finally took it to a neighboring city to a heavy duty truck drivetrain specialist who found the driveline was slightly unbalanced and the carrier bearing was completely gone. I drove it and found the vibration was slightly better but still there. They drained the diff and found the oil looked like mercury and took apart the diff. Bearings and track loc were toast. I have a Ford warranty but wonder how this will work. The truck is still in the shop with an estimated total of $4k in repairs.
If there was a housing issue, I want to inform them before it is reassembled and eventually have the same issue again.
Anyone have any input?
Thanks,
Shane
You mentioned having a "Ford warranty." Is this an "extended" warranty through what is now called Ford Protect?
I'm guessing that the Ford dealer was wanting some weight on your chassis, not specifically a pallet of concrete, but at least 2,800 more pounds of weight (assuming your steel skirted flat bed is 1,200 lbs) in order to evaluate the pinion angle at optimal designed operational ride height.
After Dana and Eaton parted ways, Dana repurposed their old trademarked name Trac-Lok (formerly describing a friction disc based limited slip in the 1970's and '80's) into describing Dana's me-too copycat version of Eaton's Detroit TrueTrac helical gear based limited slip, which Dana/Spicer introduced in 2020 as Trac-Lok.
Dana's re-use of the name Trac-Lok to describe two entirely different limited slip systems is confusing, so I just wanted to check in with you to confirm that the Trac-Lok components that the independent shop claims are trashed in your strewn apart rear differential are indeed a helical gear based system, and not a friction disc set up.
I do not know what limited slip components are in the differential, however, I can certainly ask. They did mention that the unit was 60 lbs and they could not get it overnighted so it would be a few days before it arrived. I understand this rear end to be a Dana M300. It has 4:88 gears
The GM of the dealer said I needed to buy the weight before he would test it, which is ridiculous because it did it loaded or unloaded. If those were his requirements, then it should be up to them to provide said weight.
As far as the warranty, it was the Ford extended warranty out until 175k. I do not remember the name of it, but it wasn't called Ford Protect when I bought it in 22 but it was their premium product at the time.
I did not buy the truck from them; I bought it from Rush medium duty truck center in Denver.
As such, your driveline is spinning faster at all times, in all situations, which could be useful to keep in mind, when comparing what you are experiencing with others.
In 2001, Ford changed a component in their automatic transmission of that era, and the design problem with that component manifested in higher RPM gasoline engine equipped trucks, but did not always manifest in lower rpm diesel equipped trucks, even though the same problematic component existed in the transmissions of both trucks. Ford initially issued a stop sale and recalled the gas trucks, while letting the diesel owners twist in the wind without resolution until their warranties expired.
I am not saying that this is the case here. I'm just saying that as you seek resonant experiences from other truck owners who you find have had similar concerns (as you mentioned in Post #1), keep in mind what engine they have, as that effects the amounting of spinning the driveline has to do per mile, which effects wear rate of the carrier bearing and parts internal to the differential.
Does the fine print of your extended warranty agreement have any pre-authorization requirements for non dealership service procedures?
No idea about the pre auth, it would not surprise me if they try to weasel out of paying, it's what most large corporations do now days.
Last edited by lynkage; Yesterday at 08:35 PM.












